Drill-chuck.



PATENTED JULY 3.1906. 0 M. MOWAT. DRILL CHUCK.

Q91 Fawn): ZWmm,

chick-body, illustrating the shank of a drill UNITED STATES PATENT OFFICE.

Specification of Letters Patent.

Patented July 3, 1906.

Application filed May 11,1905. Serial No. 259,896.

To all whom, it may concern:

Be it known that I, OLIVER M. MOWAT, a citizen of the United States of America, residing at McKeesport, in the county of Allegheny and State of Pennsylvania, have invented certain new and useful Improvements in Drill-Chucks, of which the following is a specification, reference being had therein to the accompanying drawings.

This invention relates to certain new and useful improvements in drillchucks; and the invention has for its object to provide a chuck-body wherein novel jaws are employed for gripping and retaining the shank of a drill within the chuck-body.

Another object of this invention is to provide a chuck-body in which a substantially rectangular shank portion of a bit or drillcan be easily and quickly secured, novel means also being provided in connection with a chuck-body for accurately holding drills or bits having tapering or cylindrical shank portions, also drills or bits having flattened surfaces or angularly-disposed faces.

Briefly described, my improved drill-chuck consists of a body having a plurality of jaws mounted therein adapted to be adjusted by an operating-ring carried by the chuck-body. Some of the jaws of the chuckbody are provided with lugs adapted to engage fiat surfaces formed upon the shank of a drill or bit, and in order that the jaws may be adjusted I have cut away a portion of the chuck-body to permit of the movement of the jaws carrying the lugs.

The above construction will be hereinafter more fully described and then specifically pointed out in the claims, and, referring to the drawings accompanying this application, like numerals of reference designate corresponding parts throughout the several views, in which Figure 1, is a perspective view of my improved chuck-body, partly broken away to illustrate the interior formation of the same. 2 is a transverse sectional view of the clamped therein, the operating-ring being re moved from the chuck-body. Fig. 3 is a side elevation of the shank portion of a drill, illustrating my improved jaws clamping said drill. Fig. 4 is a side elevation view of the chuck-body, partly in section; and Fig. 5 is a detail perspective view of a portion of my improved jaws.

To put my invention into practice, I employ the ordinary and well-known form of chuck-body 1, which is preferably made of machinery-steel and is provided with tapering ends 2 and 3. The tapering end 3 of the chuck-body is provided with a tapering opening or recess 4:, adapted to receive the spindle of a drilling-machine, whereby it can be revolved. The chuck-body is provided with a plurality of jaw-openings 5 5 5, which are angularly dis osed to the longitudinal axis of the chuckody. The ends of the jaw-openings terminating in the tapering end 2 form a substantially three-winged opening, the walls of said opening intersecting and providing a common opening in the tapering end 2 of the chuck-body. The opposite ends of the j awo enings terminate in the periphery of the c uck-body adjacent to the tapering end 3 thereof, as clearly illustrated in Fig. 1 of the drawings. In the jaw-openings of the chuckbody are mounted jaws 6, which are made of tool-steel carefully hardened and tempered. Each jaw consists of a cylindrical body portion, the one end of which is cut away to form angularly-disposed surfaces 7 and 7, and the opposite end of the jaws are cut away, as indicated at 8, to form threads 9, that are formed transversely of the jaw and upon an arc corresponding to the circumference of the chuck-body. The jaws are adapted to be mounted in the openings 5 of the chuck-body and the threaded portion of each jaw is adapted to engage a threaded ring 10, mounted in an annular groove 11, formed in the chuck-body, said groove intersecting the j awopenings and permitting the threaded ring to engage the threads 9 of each of the jaws. A

knurled ring 12 is placed upon the chuck-.

body in engagement with the threaded ring, whereby said ring can be readily revolved to move the jaws within their respective openmgs.

The above construction, as described, is common to chuck-bodies at present used, and my invention resides in the construction of the jaws and the chuck-body now to be described in connection with the chuck-body heretofore mentioned.

Heretofore in chuck-bodies whereinthree gripping-j aws were employed and manually ICC operated it has been impossible to grip the shank portions of drills having rectangular or flattened shanks without removing the jaws employed for gripping a cylindrical shank portion and employing specially-constructed jaws for rectan ular shanks. In view of the above facts I have devised jaws for chuck-bodies which are capable of gripping cylindrical shanks, as well as shanks of a rectangular form or provided with flat surfaces. In Figs. 2, 3, and 5 of the drawings I have illustrated my improved jaws, and the invention resides in providing one of the angularly-disposed surfaces 7 of two of the aws with lugs 14 14. These lugs are preferably formed at the rear ends of the angularly-disposed surfaces 7, and the faces 15 15 of said lugs are adapted to lie in a plane horizontal with the adjacent angularly-disposed surface 7 of saidjaws.

In the ordinary form of chuck-body the jaw-openings lie at angles substantially one hundred and twenty degrees from one another, and in order that my improved jaws may be advantageously used for the purposes heretofore mentioned it is necessary that two of the openings in which my improved jaws are to be mounted should be constructed closer together or at a greater angle from the third opening of the chuckbody. This construction is necessary that the angularly-disposed surfaces 15 of the jaws can be positioned in lanes parallel to one another, whereby the s iank of a drillcan be properly gripped. In Fig. 2 of the drawings I have illustrated the shank of a drill 16, which is cylindrical and is provided with diametrically-opposed flat surfaces 17 17. These flat surfaces correspond to the sides of an in scribed square of a circle having a diameter equivalent to the cylindrical shank of the drill. In order that the angularly-disposed surfaces 15 15 of the lugs 17 may embrace the flat surfaces of the drill, I have found. it necessary to position the jaw-openings 5 5, carrying my improved jaws, closer together in order that the lugs carried bythe jaws positioned within said openings will lie in parallel planes.

To accommodate jaws constructed in ac cordance with my invention within the chuck-body 1, I have found it necessary to cut away the chuck-body upon each side of the openings carrying the speciallyconstructed aws. The cut-awa portion of one of said openings is illustrate in Fig. 1 of the drawings, and by comparin this figure with Fig. 2 of the drawings it will )e observed that the portion cut out of the chuck-body is substantially triangular in form, as desi nated by the reference-numeral 18. It is only necessary to cut away the chuck-body a short distance 11 on each side of the jaw-openings, as it is seldbmnecessary to adjust the jaws a great distance in order to clamp the flat surfaces of a drill-shank. In placing the jaws within the chuck-body they are preferably placed in the openings 5 5 at the tapered end 2 of the chuck-body, one jaw being placed in at a time.

It is obvious that I have only constructed two of the jaws of the chuck-body in accordance with my invention, it being only necessary to hold the shank of the drill upon two sides when a third jaw is engaging the periphery of the drill-shank, as indicated at 19. The jaws can also be used'for gripping tapered shanks, in which instance the sharp edges 20, formed by the angularly-disposed faces 7 and 7 of the jaws, are adapted to engage the periphery of the drill-shanks.

From the foregoing it will be observed that when the shank of a drill or bit is placed within the chuck-body and the operatingring rotated to move the jaws 6 into engagement with the shank of a bit or drill said shank will be centered within the chuckbody, and after the jaws have once gripped the shank it will be impossible for any longitudinal movement of the drill-shank within the chuck-body to take place. In oonnection with my improved jaws and chuck-body I may employ a fourth jaw, which may be positioned to engage the peripheral surface of a shank while two-jaws constructed with lugs 14 14 may be engaging the flattened surfaces of the shank.

From the above description it is thought that the construction, operation, and advantages of a chuck-body constructed in accordance with my invention will be apparent without further description, and. it will be understood that various changes in the form, proportion, and minor details of construction may be resorted to without departing from the spirit of-the invention or-sacrificing any of the advantages thereof.

What I claim, and desire to secure by Letters Patent, is

1. The combination with a chuck-body having converging openings formed therein and an operating-ring, of jaws mounted in said openings and adjustable by said ring, the ends of said jaws being provided with angularly-disposed faces, one of said faces on one jaw confronting a face on another jaw lyin in a plane parallel therewith, lugs carried oy the said two jaws at the rear portion of said faces, said lugs having two of their faces in parallel planes.

2. The combination with a chuck-body having three converging openings formed therein, two of said 0 enings being closer together than each of t e same'is to the third opening, of jaws mounted one in each of said openings, the ends of said jaws being formed with angularly-disposed faces, means for adjusting said jaws, and lugs carried by the two jaws which are in the closer relation, said lugs having two of their faces in parallel just said jaws. planes. In testimony whereof I affix my signature h 3 The combinatiim 5L huckgbody, in the presence of two Witnesses.

avingata ering en ,sai 0 y eing ormed with openiilgs converging in the direction of OLIVER MOWAT' the longitudinal axis of the body and toward Witnesses: a common line, jaws mounted in said open- HARRY V. GERMAN. ings, lugs carried by said jaws and having E. E. POTTER.

confronting parallel faces and means to ad- IO 

